Does the SARS-CoV-2 pandemic actually cause dysfunctional dietary behavior? A comment on Dinse et al. (2023)

Based on a recent cross-sectional study using self-report questionnaires, Dinse and colleagues (2023) claim that this study shows that "the SARS-CoV-2 pandemic causes a dysfunctional dietary behavior" (title) and that the "data clearly show that psychological burdens affect an individual's dietary behavior" (abstract). This commentary argues that these claims are unfounded. Specifically, it highlights some issues regarding the statistical analyses that refer to artificial categorization of continuous variables, use of covariates, and interpreting differential associations between two variables as a function of third variables, which would require formal tests of interaction effects. Importantly, not only the cross-sectional nature of the study but also the wording used in the questionnaires prevents drawing any causal inferences about associations between study variables. Thus, the results of this study neither indicate that the SARS-CoV-2 pandemic causes dysfunctional dietary behavior nor that such a dietary behavior is affected by psychological distress.